When and How Often to Sharpen Lawn Mower Blades Sharpening lawn mower blades is an important part of farm equipment repair that many homeowners overlook. Dull blades can cause frayed grass, uneven cuts, and extra strain on the mower. It is recommended to sharpen the blades every 20 to 25 hours of use. At Diamond B Tractors & Equipment, we believe small maintenance steps can prevent bigger repairs. If your mower is not cutting cleanly, visit our blog to learn more. https://vocal.media/lifehack/how-many-times-a-year-should-you-sharpen-lawn-mower-blades